How to dilute RSO for edibles

Howdy all. I have some RSO made from ethanol and am looking to dilute it into more volume for dosing.
Alcohol is the obvious choice but I was thinking Vegetable Glycerin to also use in vape cart.

Its a syringe full of 800 mg THC (been decarbed) so it should be pretty straight forward. Hoping a stonner would shed a lighter on it for me.

C8

Medium Chain Triglycerides? That is a thought I could then divide them and dose by weight vs volume.
Cant use those in a vape pen however.

Why cant you use c8 or mct in vape carts?

Sweet I can? I hate polypropylene glycol. I just thought the coconut oil stuff was great edibles alone.